To provide protection from network loops normally requires the use of smart or managed switches which support Spanning Tree Protocol. These switches are more expensive than simple Unmanaged switches and also require configuration to enable this feature. For users unfamiliar with network configuration and who only require a small network with loop protection, installation of a managed solution might be daunting task, however the GS920 series of unmanaged Gigabit switches provides a simple solution to this problem.
These Ethernet switches use simple DIP switches on the front panel to select or deselect the Loop Protection feature. Enabling the feature ensures that should a loop be created, one network ports will be temporarily disabled thus removing the offending loop. Without this feature, should a loop were to occur, then network would crash as data would continue to circulate continually around the network in a data storm.
Even if the network consists of only one switch (GS920 Series switches are available with 8, 16 and 24 ports), the Loop Protection feature can be enabled.
For larger networks involving multiple switches, users can enable the loop protection feature on all the GS920 series switches and loop protection will continue to operate. When a loop is detected, one port will be disabled to prevent the loop. Imagine a network with three switches, when a loop occurs 6 ports are involved in that loop – two on each switch. Users however will not know which port has been blocked to resolve the loop. The actual port which is disabled is controlled by specific parameters of the switch, and knowing these parameters and positioning the switches in the network accordingly can help users create a better network. It would not seem sensible to block a port connecting users to a server, but a more sensible solution would be to block a different port on the network. Knowing the parameters of the switches in the network would allow a user to determine which port would be blocked, and thus connect the switches and server to minimize disruption should a loop occur. Details on the switch parameter, and how to configure the network, can be found in the installation guides for the GS920 Series switches.